Author

Abstract

In this research, has been studied the possibilities of replacing the refrigerant R-12 by R-134a and compare their thermal performance when working with the following variables (air cooling condenser, water cooling condenser, changing the length of the capillary tube).
The results shows that in the system worked with refrigerant R-12 and air or water cooled condenser the decreasing of the length of the capillary tube from 1.92m to 1.44m will lead to increase the coefficient of performance ,whereas the increasing of the length to 2.4 will lower the coefficient of performance .As For R-134a and air or water cooled condenser the decreasing of the length of the capillary tube from 1.92m to 1.44 will decrease the coefficient of performance. While the increase of the length to 2.4m will lead to increase the coefficient of performance.
That replacing the refrigerant R-12 by R-134a requires changing the compressor and oil used to stability the work of the cooling system. The results also show that replacing the refrigerant with air or water condenser and using the two lengths 2.4m and 1.92 will lead to increase of the coefficient of performance .The length 1.44m is working to decrease the coefficient of performance.